Oh this legend is bugging me so much. I'm trying to make sense of something we barely have any information about. Ode to Joy the speculation, it gets the brain working on this sunday morning :P.
Right, been thinking some more :P. In the legend, are they talking about zekrom and reshiram being owned by each of the brothers or are they talking about White Kyurem and Black Kyurem? I only reason I thought of this because they both have similar characteristics so there may be some confusion between the legend itself and the modern understanding of the legend.
If it was infact White Kyurem and Black kyurem that fought, isnt it possible that maybe, just maybe (maybe 0.0001% chance lol), that the original kyurem that we see in Giant Chasm in BW is infact the ultimate dragon but it is withered because these two formes (Black kyurem and White kyurem) was virtually ripped from it from the Brother's fighting.
Oh these theories are probably so wrong, but it is fun when you have a trail of thought and you follow it

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